JP2013541374A - X-ray system and method - Google Patents

Abstract

An X-ray system transmits an X-ray tube having an anode and a cathode, a sensor configured to sense a condition caused by operation of the X-ray tube, and a signal to the panel based at least in part on the sensed condition And a communication device, wherein the panel is configured to receive the radiation and generate an image signal in response to the received radiation. The imaging method includes sensing a state caused by the operation of the X-ray tube and transmitting a signal to the panel in response to the sensed state, the panel generating an image signal in response to radiation. Configured and includes a plurality of image elements.
[Selection] Figure 1

Description

  The present invention relates to systems and methods for obtaining X-ray images.

  X-ray imaging devices using X-ray tubes and films are commonly used in many industries for generating X-rays, especially in the field of medical X-ray imaging. An existing practice is to place the patient between the x-ray tube and the film. The x-ray technician then positions the patient, sets up the x-ray device, and exposes the film using radiation from the x-ray device. The act of exposing the film is a two-step process using a hand switch. Specifically, the X-ray engineer pressed the hand switch button halfway, (1) rotated the anode in the X-ray tube at full speed, and (2) calibrated the state of the cathode in the X-ray tube from the standby current. Change to preheat level. The preheat level is calibrated to the filament current required to produce a given beam current at an energy output selected by a generator coupled to the x-ray tube.

  Once the x-ray tube and generator are stable, the technician gets a visual signal from the generator that the tube is ready to generate x-rays for exposure to the patient and film. Since the film is always ready to receive x-rays, the engineer can then press the button completely, so that the generator is activated to deliver energy to the tube, thereby pre- X-rays are generated as programmed.

  In many applications, including medical and industrial imaging, digital X-ray imagers for converting X-rays into images have replaced film. The applicant of this application concludes that it would be desirable to have a new x-ray system and method for obtaining digital x-rays.

  According to some embodiments, an x-ray system includes an x-ray tube having an anode and a cathode, a sensor configured to detect the amount of radiation generated from the operation of the x-ray tube, and detected by the sensor. A communication device for transmitting a signal to the panel according to the amount of radiation emitted. By way of non-limiting example, the amount of radiation may be in the form of light, radiation, or other energy emitted from the source.

  According to other embodiments, an x-ray system includes an x-ray tube having an anode and a cathode, a sensor configured to sense a condition caused by operation of the x-ray tube, and at least partially in the sensed condition. A communication device for transmitting a signal to the panel based on, wherein the panel is configured to receive the radiation and generate an image signal in response to the received radiation.

  According to another embodiment, an imaging method includes sensing a condition caused by operation of an x-ray tube and transmitting a signal to the panel in response to the sensed condition, the panel receiving radiation. In response, the image signal is generated and includes a plurality of image elements.

  Other and further aspects and features will become apparent upon reading the following detailed description of the embodiments, which are intended to be illustrative of the invention and are not intended to be limiting.

  The drawings illustrate the design and utility of the embodiments, and like elements are referred to by common reference numerals. These drawings are not necessarily drawn to scale. In order to better understand how the above and other advantages and objectives can be obtained, a more specific description of embodiments is provided, which are illustrated in the accompanying drawings. These drawings are merely representative of exemplary embodiments and, therefore, should not be considered as limiting the scope thereof.

1 illustrates an X-ray system according to some embodiments. 6 illustrates another X-ray system according to another embodiment. 6 illustrates another X-ray system according to another embodiment. 6 illustrates another X-ray system according to another embodiment. 6 illustrates another X-ray system according to another embodiment. 6 illustrates another X-ray system according to another embodiment. 2 illustrates a graph showing a relationship between a photodetector signal and time. It is a one part enlarged view of the graph of FIG. 7A. 2 illustrates a graph showing the relationship between the derivative of a photodetector signal and time. It is a one part enlarged view of the graph of FIG. 8A. 2 illustrates an order of exposure according to some embodiments. FIG. 2 is a block diagram of a computer system architecture that can implement the embodiments described herein.

  In the following, various embodiments will be described with reference to the figures. Note that the figures are not drawn to scale, and elements of similar structure or function are represented by like reference numerals throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the embodiments. They are not intended to be an exclusive description of the invention or a limitation on the scope of the invention. Moreover, the illustrated embodiments need not have all the aspects or advantages shown. The aspects or advantages described with a particular embodiment are not necessarily limited to that embodiment, and can be practiced in any other embodiment, even if not so exemplified.

  FIG. 1 illustrates an x-ray system 10 according to some embodiments. The X-ray system 10 includes a generator 12, an X-ray tube 14, and a panel 16. The generator 12 is configured to provide power to the X-ray tube 14 during use of the X-ray system 10. The x-ray tube 14 includes a container 28 that defines a chamber 30, an anode 32 and a cathode 34 located within the chamber 30, and a rotating device 36 for rotating the anode 32. The cathode 34 is configured to receive voltage from the generator 12 during use and functions as an electron gun for delivering electrons toward the anode 32. The rotation device 36 includes a rotor 38 and a stator 40. The rotating device 36 is configured to rotate the anode 32 when electrons are accelerated from the cathode 34 toward the anode 32. Such a configuration allows electrons to strike different parts of the anode 32, thereby reducing the amount of heat that would be generated when the anode 32 was stationary.

In some embodiments, the anode material may be secured to a rotating disk coupled to the rotating device 36. In other embodiments, the anode 32 may be formed as part of a rotating disk. The target anode 32 can include a variety of materials having suitable mechanical, thermal, electrical, and other properties suitable for the generation of a predetermined x-ray spectrum and intensity. Examples of materials that can be used include holmium, erbium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, terbium, dysprosium, thulium, ytterbium, lutetium, barium, molybdenum, rhodium, zirconium, hafnium, tungsten, titanium, Rhenium, rhenium, molybdenum, copper, graphite, other rare earth materials and platinum group metals, and combinations thereof. A suitably stable refractory compound such as cerium boride (CeB ₆ ) and other compounds formed from any of the above materials can be used for the anode 32.

  The panel 16 includes a plurality of imaging elements 50. Each of the imaging elements 50 of the panel 16 is configured to receive radiation and generate an image signal in response to the received radiation. In some embodiments, the panel 16 includes a conversion layer made from a scintillator element, such as cesium iodide (CsI), and a photodetector array (eg, a photodiode layer) coupled to the conversion layer. The conversion layer generates photons in response to radiation, and a photodetector array including a plurality of detector elements is configured to generate electrical signals in response to photons from the conversion layer. The panel 16 can have a curved surface (eg, a partial arc). Such a configuration is advantageous in that each of the imaging elements of panel 16 is located at substantially the same distance from the radiation source. In alternative embodiments, the panel 16 may have a surface that has a straight surface or other shape. Panel 16 can be made from amorphous silicon, quartz and silicon wafers, quartz and silicon substrates, or flexible substrates (eg, plastic) and is known in the art of making flat panel technology or imaging devices. It may be constructed using some other technique. In alternative embodiments, panel 16 may use a different detection scheme. For example, in an alternative embodiment, instead of having a conversion layer, the panel 16 may include a photoconductor that generates electron-hole pairs or discharges in response to radiation.

  In the illustrated embodiment, the x-ray system 10 also includes a photodetector 60 that is coupled to the x-ray tube 14. Photodetector 60 is configured to detect light generated from activation of cathode 34. As shown in the figure, the container 28 has an opening that allows light generated from activation of the cathode 34 to exit therethrough so that light can be detected by the photodetector 60. 62. In some embodiments, the container 28 may be made of glass, thereby providing more options for installing the photodetector 60. The photodetector 60 and the container 28 are located in the X-ray tube housing 64. In other embodiments, the container 28 may be part of the x-ray tube housing 64 or an extension. In a further embodiment, the photodetector 60 may not be completely in the X-ray tube housing 64. Alternatively, the photodetector 60 may extend partially through the wall of the x-ray tube housing 64 or may be located outside the x-ray tube housing 64 (in which case, The x-ray tube housing 64 may include an opening to allow light generated from the activation of the cathode 34 to exit there).

  As used herein, the term “photodetector” can detect radiation (light, radiation, heat, etc.) or can detect any feature associated with radiation. Note that any possible sensor may be meant. Sensor 60 may be implemented using different technologies in different embodiments. For example, sensor 60 may be implemented using silicon, GaAs, aSi, CdTe, or using any of other photodiodes. In other embodiments, thermopile (s) may be used to implement sensor 60. In further embodiments, the voltage output or current output of the photodiode may be used to generate the output by the sensor 60. In other embodiments, the sensor may be a current sensor coupled to a current lead that transmits current to the cathode 34.

  The X-ray system 10 also includes an A / D converter 70, an adjustment electronic device 72, and a signal transmitter 74 that are connected to the photodetector 60. The A / D converter 70 is configured to convert the signal (s) from the photodetector 60 into a digital format. The adjustment electronics 72 receives the signal (s) from the A / D converter 70, processes the signal (s) according to a predetermined logic / algorithm, and outputs the signal (s) from the A / D converter 70. ) To generate an output signal. The conditioning electronics 72 may be implemented using hardware, software, or a combination of hardware and software. For example, in some embodiments, the conditioning electronics 72 may be implemented using a processor, computer, or other device with signal processing capabilities. The transmitter 74 is configured to transmit an output signal to a receiver 80 coupled to the panel 16. The panel 16 is configured to reset the image element 50 in accordance with the signal received by the receiver 80, integrate the signal to generate the image signal, and read the image signal. By way of non-limiting example, each of transmitter 74 and receiver 80 may be a high frequency device, an infrared device, an ultrasound device, or a Bluetooth device. In further embodiments, transmitter 74 and receiver 80 may be implemented using one or more wires or one or more optical fibers that connect from conditioning electronics 72 to panel 16.

  In the illustrated embodiment, the components 60, 70, 72, 74 are shown as separate components. However, in other embodiments, the A / D converter 70 may be part of the sensor 60. In further embodiments, the A / D converter 70 and the adjustment electronics 72 may be part of the sensor 60. In other embodiments, the adjustment electronic device 72 may be a part of the panel 16 or a component physically connected to the panel 16.

  The x-ray system 10 also includes a handheld control 88 having a control button 90 operably coupled to the x-ray tube 14. The controller 88 is configured to operate the X-ray tube 14 during use. Specifically, the anode 32 can be rotated by the rotating device 36 by pressing the button 90 of the control unit 88 halfway. After rotating the anode 32 to the desired speed, the button 90 of the controller 88 can then be fully depressed to accelerate electrons from the cathode 34 to the anode 32.

  During use of the X-ray system 10, the generator 12 supplies an initial current to the cathode 34 to warm the cathode 34 and place the cathode 34 in a “standby” mode. The control button 90 can then be depressed halfway to rotate the anode 32 and cause the generator 12 to deliver additional current to the cathode 34, thereby placing the cathode 34 in a “ready to fire” mode. The additional current raises the cathode 34 temperature from a warm-up (or standby) level to a pre-calibration level. The operator can further activate the button 90 and press the button 90 completely. In the illustrated embodiment, depressing the control button 90 completely causes the voltage generator 12 to supply an activation current to the cathode 34, which results in electrons being accelerated from the cathode 34 to the rotating target anode 32. The Specifically, due to the potential generated between the cathode 34 and the anode 32, the electrons are accelerated toward the anode 32 to form a beam 90 of electrons. The beam 90 may be a continuous beam or alternatively a pulsed beam. X-rays are generated by the interaction of the electron beam 90 and the anode 32. While most of the generated X-rays are confined by the container 28 and / or the X-ray tube housing 64, the X-ray beam 92 leaks out of the X-ray window 94. In the illustrated embodiment, the anode 32 has an annular or circular configuration. When X-rays are generated, the rotating device 36 rotates the anode 32 such that the electron beam 90 impinges on different positions on the anode 32, thereby preventing the anode 32 from overheating.

  In the illustrated embodiment, activation of the cathode 34 is sensed by the sensor 60 and a signal is transmitted to the conditioning electronics 72. When adjustment electronics 72 receives a signal from sensor 60, adjustment electronics 72 then transmits a control signal to panel 16 via device 74, thereby controlling the operation of panel 16. In the illustrated embodiment, the control signal is used to cause the panel 16 to reset its imaging element 50. However, as used herein, the term “control signal” is not limited to signals for directly controlling the operation of panel 16 and is used in any process for operating panel 16. Note that this may mean any information. Further, as used in this specification, the act of controlling the operation of the panel 16 is not limited to the act of physically operating the panel 16, and information used in any process for operating the panel 16. Providing may be included.

  In one implementation, the conditioning electronics 72 is configured to determine whether the signal from the sensor 60 is at or above a predetermined threshold (which may be related to the activation of the cathode 34). If the signal is at or above a predetermined threshold, the conditioning electronics 72 then transmits a control signal to the panel 16. In the illustrated embodiment, the panel 16 is configured to reset the imaging element 50 after a predetermined period of time after the condition is sensed by the photodetector 60. In another embodiment, the panel 16 is configured to reset the imaging element 50 after a predetermined period of time has elapsed since the panel 16 received a signal from the adjustment electronics 72. In a further embodiment, the adjustment electronics 72 may be part of the panel 16, in which case the panel 16 captures images after a predetermined period of time has elapsed since the adjustment electronics 72 generated the signal. Configured to reset element 50. In any of the embodiments described herein, the predetermined period may be at least 100 milliseconds, or other values such as any value between 0 and 0.5 seconds. In any of the embodiments described herein, the panel 16 is notified of an impacting x-ray at least 0.35 seconds before the impacting x-ray occurs. This allows the panel 16 to have sufficient time to reset the image element 50. In a further embodiment, when the panel 16 receives a signal from the adjustment electronics 72, the imaging element 50 is immediately reset without waiting for any predetermined period.

  In some embodiments, after the panel 16 resets its imaging element 50, the panel 16 is also configured to perform signal integration and read the image signal to obtain an image signal. The panel 16 may be configured to perform signal integration based on a fixed integration period or a variable integration period. In some embodiments, the variable integration period may be based on a state sensed by sensor 60. In some embodiments, the panel 16 may include a processor for determining a variable integration period based on the sensed state (s). For example, in some embodiments, the sensor 60 can send a signal that X-rays are ON, and then again that they are OFF. The panel can then respond by ending the integration period early, and by counting the clock period, it can record the actual integration time used in terms of its internal clock frequency. The panel can then acquire an offset image (dark image) using the same integration period and use the offset image to modify the X-ray image.

  The configuration of the X-ray system 10 (eg, the shape, dimensions, design, and arrangement of various components) should not be limited to the examples illustrated in the figures, and the X-ray system 10 may have other configurations Note that you can. For example, in other embodiments, the x-ray system 10 may have different shapes.

  In other embodiments, the X-ray system 10 may optionally further include a shielding plate 120 and a mirror 122 (FIG. 2). The shielding plate 120 is for blocking radiation toward the photodetector 60 in order to protect the photodetector 60 from damage due to radiation, and the mirror 122 reflects light toward the photodetector 60. Is for. The mirror 122 may have a linear or curved configuration. The operation of the X-ray system 10 of FIG. 2 is similar to that described with reference to the embodiment of FIG.

  FIG. 3 illustrates another X-ray system 10 according to another embodiment. The X-ray system 10 of FIG. 3 is similar to the embodiment of FIG. 1 except that the photodetector 60 is not located outside the container 28. Instead, the photodetector 60 is located at least partially inside the container 28. With such a configuration, the photodetector 60 can detect light generated from the operation of the cathode 34 more efficiently. The operation of the X-ray system 10 of FIG. 3 is similar to that described with reference to the embodiment of FIG.

  FIG. 4 illustrates another X-ray system 10 according to another embodiment. The X-ray system 10 of FIG. 4 is similar to the embodiment of FIG. 1 except that the photodetector 60 is located within the shaft 200 of the cathode 34. Such a configuration eliminates the need to create a separate opening through the wall of the housing 28 to allow detection of light by the photodetector 60. Also, because the photo detector 60 is located within the cathode shaft 200, it is less likely to be degraded by radiation generated in the chamber 30. In other embodiments, the photodetector 60 may be located at another location. For example, in other embodiments, the shaft 200 of the cathode 34 may include an optical fiber for transmitting light from within the chamber 30 to another location where the photodetector 60 is located. Photodetector 60 receives an optical signal from the optical fiber and generates a signal (for transmission to components 70, 72, and / or 74) based on the optical signal received from the optical fiber. In other embodiments, both the photodetector 60 and the optical fiber may be located within the shaft of the cathode 34. In further embodiments, the optical fiber and / or photodetector 60 is located elsewhere relative to the tube housing 64 as long as the photodetector 60 can sense the light generated from the operation of the tube 14. May be. The operation of the X-ray system 10 of FIG. 4 is similar to that described with reference to the embodiment of FIG.

  In any of the embodiments described herein, the system 10 can include another type of sensor instead of using a photodetector. For example, in any of the embodiments described herein, sensor 60 may be a thermal sensor instead of being a photodetector, or an attribute or physical change at the cathode (eg, temperature, It may be another type of sensor configured to sense a condition associated with activation of the cathode 34, such as any device that senses photon emission, current, voltage, magnetic field, light, etc.).

  In any of the embodiments described herein, the photodetector 60 replaces light with radiation generated from the operation of the x-ray tube (eg, any of the components of the x-ray tube). (Radiation emitted from manipulating) may be detected.

  FIG. 5 illustrates another x-ray system 10 according to another embodiment. The X-ray system 10 does not include the photodetector 60. Instead, the x-ray system 10 includes a current detector / sensor 300 configured to detect a current associated with the operation of the rotating device 36. During use of the X-ray system 10 of FIG. 5, the generator 12 supplies an initial current to the cathode 34 to warm the cathode 34 and place the cathode 34 in a “standby” mode. Next, the control button 90 can be depressed halfway to rotate the anode 32 and cause the generator 12 to deliver additional current to the cathode 34 such that the cathode 34 is in the “ready to fire” mode. The additional current raises the cathode 34 temperature from a warm-up (or standby) level to a pre-calibration level. The operator can further activate the button 90 and press the button 90 completely. In the illustrated embodiment, depressing the control button 90 completely causes the voltage generator 12 to supply an activation current to the cathode 34, which results in electrons being accelerated from the cathode 34 to the rotating target anode 32. The Specifically, due to the potential generated between the cathode 34 and the anode 32, the electrons are accelerated toward the anode 32 to form a beam 90 of electrons. The beam 90 may be a continuous beam or alternatively a pulsed beam. X-rays are generated by the interaction of the electron beam 90 and the anode 32. While most of the generated X-rays are confined by the container 28 and / or the X-ray tube housing 64, the X-ray beam 92 leaks out of the X-ray window 94. In the illustrated embodiment, the anode 32 has an annular or circular configuration. When X-rays are generated, the rotating device 36 rotates the anode 32 such that the electron beam 90 impinges on different positions on the anode 32, thereby preventing the anode 32 from overheating.

  In the illustrated embodiment of FIG. 5, the rotation of the anode 32 is sensed by the sensor 300 and a signal is transmitted to the conditioning electronics 72. In one implementation, different phases of AC current may be applied to different windings of the stator 40. In such a case, the onset of rotation causes an increase in current in the stator lead, which can be used to suggest that it will soon be exposed. When the adjustment electronics 72 receives a signal from the sensor 300, the adjustment electronics 72 then transmits a control signal to the panel 16 via the device 74, thereby causing the panel 16 to reset its imaging element 50. In one implementation, the conditioning electronics 72 determines whether the signal from the sensor 300 is at or above a predetermined threshold (which may be related to the maximum / or minimum operating rotational speed of the anode 32). If the signal is at or above a predetermined threshold, the conditioning electronics 72 then transmits a control signal to the panel 16. In the illustrated embodiment, the panel 16 is configured to reset the imaging element 50 after a predetermined period of time after a condition is sensed by the sensor 300. In another embodiment, the panel 16 is configured to reset the imaging element 50 after a predetermined period of time has elapsed since the panel 16 received a signal from the adjustment electronics 72. In a further embodiment, the adjustment electronics 72 may be part of the panel 16, in which case the panel 16 captures images after a predetermined period of time has elapsed since the adjustment electronics 72 generated the signal. Configured to reset element 50. In any of the embodiments described herein, the predetermined period may be at least 100 milliseconds, or other values such as any value between 0 and 0.5 seconds.

  In some embodiments, after the panel 16 resets its imaging element 50, the panel 16 is also configured to perform signal integration and read the image signal to obtain an image signal. The panel 16 may be configured to perform signal integration based on a fixed integration period or a variable integration period. In some embodiments, the variable integration period may be based on a state sensed by sensor 300. In some embodiments, as discussed similarly, panel 16 may include a processor for determining the variable integration period based on the sensed state (s).

  In other embodiments, instead of using a current detector, a magnetic sensor may be used to increase the speed of the rotor. In such a case, once the rotor speed is stable, then the tuning electronics Notify that device 72 will be exposed to panel 16 soon.

  In further embodiments, two or more features of the above embodiments may be combined. For example, in a further embodiment, the X-ray system 10 may be a sensor 60 (photodetector, thermal sensor, or any other sensor configured to sense conditions associated with the operation of the cathode 34, etc. And a current detector 300 may be included. FIG. 6 illustrates another X-ray system 10 according to another embodiment. As shown in the figure, the x-ray system 10 includes a photodetector 60 (also discussed with reference to FIG. 1) and a current detector 300 (also discussed with reference to FIG. 5). In use, the generator 12 can supply an initial current to the cathode 34 to warm the cathode 34 and place the cathode 34 in a “standby” mode. Next, the anode 32 can be rotated by pressing the control button 90 halfway. The current detector 300 is configured to sense a current associated with the operation of the rotating device 36 and transmit a first signal to the conditioning electronics 72. Current is also transmitted to the cathode 34 by pressing the button 90 halfway so that the cathode 34 is in the “ready to fire” state, raising its temperature from the warm-up level to the pre-calibration level. The sensor 60 is configured to sense a condition associated with the cathode emission condition and to transmit a second signal representative of the sensed condition to the conditioning electronics 72. In the illustrated embodiment, depressing the control button 90 completely causes the voltage generator 12 to supply an activation current to the cathode 34, which results in electrons being accelerated from the cathode 34 to the rotating target anode 32. The

  When adjustment electronics 72 receives the first signal from current sensor 300 and / or the second signal from sensor 60, adjustment electronics 72 then sends a control signal to panel 16 via device 74. Transmit, thereby causing the panel 16 to reset its imaging element 50. In some embodiments, after the panel 16 resets its imaging element 50, the panel 16 is also configured to perform signal integration and read the image signal to obtain an image signal. The panel 16 may be configured to perform signal integration based on a fixed integration period or a variable integration period. In some embodiments, the variable integration period may be based on a state sensed by sensor 60, a state sensed by sensor 300, or both states sensed by sensors 60, 300, respectively. In some embodiments, panel 16 may include a processor for determining a variable integration period based on the sensed state (s), as previously described as well. Other features described in the previous embodiment may be implemented in the embodiment of FIG.

FIG. 7A illustrates a graph of data collected using an embodiment of the x-ray tube 10. The graph shows the value of the signal seen by the photodetector 60 when the current delivered to the cathode 34 is increased from the standby level to the preheat level. The filament is used as a source of electrons, and the emission of electrons from the cathode 34 filament is exponentially temperature dependent, so when the cathode filament goes from standby to preheated, the filament temperature increases considerably. To do. Amount of radiation from the filament is proportional to T ^4. As shown in the figure, the signal seen by the photodetector 60 stabilizes after about 1.5 seconds. FIG. 7B is an enlarged view of the first few seconds after pressing the control button 90 of the X-ray tube 10 halfway, where all signals are substantially the same for the first 250 milliseconds and their final It shows that a difference appears in the signal depending on the value. Different values (eg, peak voltage kVp applied to the tube, beam current mA, exposure time, etc.) are pre-programmed in the X-ray system 10 (eg, in the adjustment electronics 72) using a calibration procedure. In general, for a given mA of beam current, as the kV energy level from the generator 12 increases, the required filament current and thus the photodetector signal becomes lower. Also, at a constant kVp, the filament current increases with increasing mA. FIG. 8A shows some of the photodetector signals selected from FIG. 7A and the derivatives of these signals. The derivative shows a sharp positive peak at the start of increasing filament current and a sharp negative peak when the filament current returns from the preheat value to the standby value. FIG. 8B is an enlarged view of the first few seconds after the control button 90 of the X-ray tube 10 is pressed halfway. The shape of the curve (s) shown may be used to determine the impacting x-rays. For example, in the case of a non-derivative, the system may be configured to apply an over-threshold detector to ascertain when the filament current has risen and then dropped. In such a technique, the size of the signal depends on the selected kVp and mA, which depend on the body part being imaged. In other embodiments, the derivative of the signal may be used, which has the advantage that the peak value is not very dependent on kVp and mA. As a result, the system can operate more reliably. In some embodiments, the conditioning electronics 72 may include a smoothing filter, a derivative of the signal, or other processing to remove the spurious signal and prepare the signal to be transmitted to the control device of the panel 16. Good.

  FIG. 9 illustrates an exposure method 400 that can be performed using any of the embodiments of the X-ray system 10 according to some embodiments. Once the operator decides to perform the exposure (step 402), the operator then turns on the generator 12 (step 404). The generator 12 then sends a standby current (eg, 2 amps) to the cathode (or filament) 34 to warm the cathode 34. The operator can use imaging techniques including radiographic imaging, fluoroscopic imaging, and cine imaging (which is a higher-dose fluoroscopic imaging technique used to record video sequences for later analysis). One of these can be selected (step 406). Next, the operator sets the energy level of the generator 12 (step 408), sets the mA of the beam current (step 410), and sets the time of the radiation pulse (step 412). In some cases, the time of the pulse is set by the operator on the console, depending on the body part being imaged. The length of the beam pulse, along with kVp (energy) and mA (tube current) is part of what defines the imaging technique.

  Next, the operator presses the button 90 of the control unit 88 to a first position (for example, a half-pressed position) (step 420). In response to pressing the button 90 to the first position, the anode 32 begins to rotate (step 422) and the emission current is delivered to the cathode (filament) 34 (step 424). In one implementation, emission current is delivered by increasing the current delivered to the cathode 34 from a standby current to a preheat current (eg, 4-6 amps). As previously discussed with reference to FIG. 7A, when the emission current is delivered to the cathode 34, the signal seen by the sensor 60 increases and then stabilizes. The rotation speed of the anode 32 may be any of 3600 to 9000 rpm or other values. In some embodiments, the system is configured to allow the operator to select a speed range for the rotor 38 that corresponds to a half activation of the button 90. For example, in some embodiments, the system may allow the operator to set the speed range from 0 Hz to 60 Hz, in which case the rotor speed increases from 0 Hz to 60 Hz when button 90 is half activated. In other embodiments, the speed range of the rotor 38 may be 0 Hz to 180 Hz, 60 Hz to 180 Hz, or other ranges.

  Next, the operator presses the button 90 to the second position (for example, the fully pressed position) (step 440). In response to pressing the button 90 to the second position, the generator 12 then applies energy to the x-ray tube 14 (step 442) so that radiation is emitted from the x-ray tube (step 444). ). In the illustrated embodiment, the energy has an energy level set by the operator at step 406.

  As shown in the figure, a pulsed radiation (Pulsed Rad) emission may optionally be provided (step 450). Since the beam is ON only for a finite period, the "radiation" emission is pulsed. The duration of the pulse is set by the operator on the console depending on the body part being imaged. The length of the beam pulse is part of what defines the imaging technique and is related to parameters such as kVp (energy), mA (tube current), and time. In some cases, the mA number (milliseconds) used to form the beam pulse may be used to indicate the delivered dose. In some embodiments, the emission of pulsed radiation may be provided at 30 fps for 1-5 seconds.

  Next, the operator releases the control button 90 (step 460) and starts the hangover mode (step 470). In hangover mode, the cathode 34 current can return to the standby current after a predetermined hangover time (step 472), and the rotor 38 may enter a standby period (0 Hz, 60 Hz, or other after a predetermined hangover time). Can be a value) (step 474). The hangover time may be a value selected by the operator. In some embodiments, the system 10 provides a user interface that allows an operator to select such a hangover time, which may be any value, for example, 0-99 seconds. During the hangover time, the cathode 34 and the rotor 38 remain in a “ready to fire” state so that the operator can create (expose) additional images by fully activating the button 90. Steps 420-444 are then repeated if the operator wishes to create additional images after the hangover time (ie, after the system 10 exits hangover mode).

  As illustrated in the above embodiment, the system 10 can notify that the panel 16 is about to be irradiated with X-rays, so that the panel 16 minimizes signal integration when no radiation is applied. This is advantageous in that the image element 50 can be automatically reset at the appropriate time so that it can be or at least reduced. System 10 is also advantageous in that it does not require modification of generator 12 to implement the features described herein. Thus, the existing generator 12 can be used with the embodiment of the system 10 described herein.

  As exemplified in the above-described embodiment, the panel 16 can prepare and wait in the integration mode according to the semi-starting state of the control unit 88. However, in some situations, the operator may press the control button 90 halfway, and may wait for a long time before the button 90 is fully activated. In such a situation, sensing by sensor 60 and / or current sensor 300 may not accurately correlate with superior x-ray emission (because the actual emission may cause the user to fully control button 90). Because it only happens when you press Further, when the user waits for a long time between the half activation and the full activation, the imaging element 50 may be reset too early.

  To address the above problem, in some embodiments, panel 16 may be configured to be in integral mode for a predetermined period of time. For example, in some embodiments, the panel 16 may be in an integration mode within 10 seconds between half activation and full activation of the button 90. In such an example, if the operator waits for 4 seconds between half activation and full activation, the panel 16 will be in integration mode for 4 seconds and will not receive radiation. However, if the operator fully activates button 90 within the next 6 seconds, radiation is delivered and panel 16 integrates the image signal generated as a result of the radiation. In other embodiments, the operator may be required to wait within a predetermined time period between half activation and full activation of the button 90. The above technique prevents the panel from staying in the integrated state for a long time, accumulating a lot of dark current, reducing the dynamic range of the panel 16 and creating artifacts. The above techniques are also advantageous in that they accommodate a very wide activation time between half activation and full activation of the control button 90.

  In other embodiments, the panel 16 may be configured to always integrate and read the signal. For example, the panel 16 may include an amorphous silicon PIN photodiode / TFT type array capable of continuously integrating signals. In one implementation, the panels 16 may be configured to read and sum frames with doses in them every second (or another predetermined period). In such an embodiment, panel 16 reads data every second even if no radiation is present (ie, even if control button 90 is not fully depressed). For example, if the operator waits for 4 seconds between half activation and full activation, the panel 16 will still read data during that 4 seconds when no radiation is present. In such a case, readings from 4 seconds are not used (in other words, the frame addition includes those obtained from radiation alone).

  In other embodiments, the panel 16 may be configured to operate at a continuous constant frame rate. In this general scenario, it is assumed that a panel that does not need to be reset (ie, a PIN / TFT array) is used. In this case, there is no dead time, and there is no need for prior notice by the panel to operate the panel 16. In use, panel 16 uses the signal from sensor 60 (or any of the sensors described herein) to determine which frames have a dose therein, and only those frames. Is added. Therefore, for example, when a moment sensor (for example, sensor 60) transmits “X-ray ON”, the panel starts summing (integrating) frames in its internal memory or another memory. Understanding that the panel is “X-ray off” completes its last frame, stops accumulating, and transmits the image (accumulated from many frames) to non-temporary memory for storage Or transmit to the screen for display. Alternatively, the addition may be performed within the workstation. In such cases, the panel may create a flag in the image data to suggest that the frame has a dose in it. Later, at the workstation, the processor may be configured to select all frames with flags and sum the frames to create an integrated dose image.

  In yet other embodiments, the panel 16 is so rapid that it can provide a reset feature in which only a fraction of the applied dose is lost. For example, in some embodiments, the panel 16 may be reset within 100 ms. In other embodiments, the panel 16 may be reset within 10 ms. In any of the embodiments, a signal from the radiation beam itself can be used to trigger a reset and transition to integration.

  In further embodiments, a sensor may be used to detect full activation of the control button 90. In such a case, (1) when the cathode is fully warmed, (2) when the anode reaches full speed, and (3) when the user control button 90 is fully depressed, the panel is in integral mode. It becomes. With such a technique, excellent X-ray emission can be accurately correlated with full activation of the control button 90.

  In the above embodiment, the system 10 has been described as having a rotating anode. In any of the embodiments described herein, the anode may alternatively be stationary. In such a case, system 10 does not include any device for rotating the anode.

  Also, the sensor for sensing the operation of the tube 14 is not limited to the example described previously. In other embodiments, the tube 14 may include other types of sensors for sensing other conditions associated with the operation of the tube 14. For example, in other embodiments, the tube 14 may include a vibration sensor for sensing vibrations that may occur when the tube 14 is activated. In other embodiments, the tube 14 may include a sound sensor for sensing sound produced by the operation of the tube 14. In still other embodiments, motion sensors may be used to sense the movement of machine components in the tube 14. In further embodiments, the tube 14 may include a sensor for sensing an electron beam formed by or emitted from the tube 14. In such a case, the detected electron beam suggests that X-rays will soon be delivered to the panel 16. In further embodiments, the tube 14 may include a sensor for sensing current delivered to the cathode 34 (eg, high current above a predetermined level) or current at the cathode 34. In such a case, the detected current suggests that X-rays will soon be delivered to panel 16. Also, other types of sensors may be used in other embodiments.

  Further, in any of the embodiments described herein, the signal (s) for controlling the operation of the panel 16 need to be transmitted directly from the tube (eg, from the tube sensor) to the panel 16. There is no. Alternatively, the signal (s) may be transmitted to the panel 16 indirectly through an intermediate device.

Computer system architecture

  FIG. 10 is a block diagram that illustrates one embodiment of a computer system 1200 upon which an embodiment of the invention may be implemented. Computer system 1200 includes a bus 1202 or other communication mechanism for communicating information, and a processor 1204 coupled with bus 1202 for processing information. The processor 1204 may be an example of the conditioning circuit 72 or may be another processor used to perform the various functions described herein. In some cases, computer system 1200 may be used to implement adjustment circuit 72. Computer system 1200 also includes main memory 1206, such as random access memory (RAM) or other dynamic storage device, coupled to bus 1202 for storing information and instructions executed by processor 1204. Main memory 1206 can also be used to store temporary variables or other intermediate information during execution of instructions executed by processor 1204. Computer system 1200 further includes a read only memory (ROM) 1208 or other static storage device coupled to bus 1202 for storing static information and instructions to processor 1204. A data storage device 1210, such as a magnetic disk or optical disk, is provided and coupled to bus 1202 for storing information and instructions.

  The computer system 1200 may be connected via a bus 1202 to a display unit 1212 such as a cathode ray tube (CRT) or a flat panel for displaying information to a user. An input device 1214 that includes alphanumeric characters and other keys is coupled to the bus 1202 for communicating information and command selections to the processor 1204. Another type of user input device is a cursor, such as a mouse, trackball, or cursor direction key, for communicating direction information and command selections to the processor 1204 and for controlling cursor movement on the display 1212. It is a control unit 1216. The input device typically has two degrees of freedom in two axes, a first axis (eg, X) and a second axis (eg, Y), so that the device is in plane. The position can be specified.

  Computer system 1200 may be used to perform various functions (eg, calculations) in accordance with the embodiments described herein. According to one embodiment, such use is provided by computer system 1200 in response to processor 1204 executing one or more sequences of one or more instructions included in main memory 1206. Such instructions may be read into main memory 1206 from another computer-readable medium, such as storage device 1210. Execution of the sequence of instructions contained in main memory 1206 causes processor 1204 to execute the processing steps described herein. Also, one or more processors may be used in multiple processing configurations to execute a sequence of instructions contained in main memory 1206. In alternative embodiments, hardwired circuitry may be used in place of or in combination with software instructions to implement the present invention. Thus, embodiments of the present invention are not limited to any specific combination of hardware circuitry and software.

  The term “computer-readable medium” as used herein refers to any medium that participates in providing instructions to processor 1204 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical or magnetic disks such as storage device 1210. Non-volatile media can be considered an example of non-transitory media. Volatile media includes dynamic memory, such as main memory 1206. Volatile media can be considered another example of non-transitory media. Transmission media includes coaxial cable, copper wire, and optical fiber, including wires with bus 1202. Transmission media can also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications.

  Common forms of computer readable media are, for example, floppy disks, flexible disks, hard disks, magnetic tapes, or other magnetic media, CD-ROMs, any other optical media, punch cards, paper tapes, holes Any other physical medium having the following pattern: RAM, PROM, and EPROM, FLASH-EPROM, any other memory chip or cartridge, or carrier wave described later in this specification, or any computer readable Including other media.

  Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to processor 1204 for execution. For example, the instructions may initially be carried on a remote computer magnetic disk. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to computer system 1200 can receive the data on the telephone line and use an infra-red transmitter to convert the data to an infra-red signal. An infrared detector coupled to the bus 1202 can receive data carried in the infrared signal and place the data on the bus 1202. Bus 1202 carries the data to main memory 1206 from which processor 1204 retrieves and executes the instructions. The instructions received by main memory 1206 may optionally be stored on storage device 1210 either before or after execution by processor 1204.

  Computer system 1200 also includes a communication interface 1218 coupled to bus 1202. Communication interface 1218 provides a two-way data communication coupling to a network link 1220 connected to a local network 1222. For example, the communication interface 1218 may be an integrated digital communication network (ISDN) card or a modem for providing a data communication connection to a corresponding type of telephone line. As another example, communication interface 1218 may be a local area network (LAN) card for providing a data communication connection to a compatible LAN. A radio link may also be implemented. In any such implementation, communication interface 1218 sends and receives electrical, electromagnetic or optical signals that carry data streams representing various types of information.

  Network link 1220 typically provides data communication to other devices through one or more networks. For example, the network link 1220 may provide a connection to the host computer 1224 through the local network 1222 or to a device 1226 such as a radiation beam source or a switch operably coupled to the radiation beam source. The data stream transported over the network link 1220 can include an electrical signal, an electromagnetic signal, or an optical signal. Signals that travel through various networks that carry data to and from computer system 1200 and that are on network link 1220 and through communication interface 1218 are exemplary carrier waves that carry information. It is a form. Computer system 1200 can send messages and receive data, including program code, over network (s), network link 1220, and communication interface 1218.

  While particular embodiments of the present invention have been illustrated and described, it will be understood that they are not intended to limit the invention to the preferred embodiments and those skilled in the art will understand the scope and spirit of the invention. It will be apparent that various changes and modifications can be made without departing from the invention. For example, the term “processor” means any device that may include one or more processing units and that is capable of performing mathematical calculations implemented using hardware and / or software. Can do. The specification and drawings are accordingly to be regarded in an illustrative rather than a restrictive sense. The present invention is intended to cover alternatives, modifications, and equivalents, which may be included within the spirit and scope of the present invention as defined by the claims.

Claims (39)

An X-ray tube having an anode and a cathode;
A sensor configured to detect the amount of radiation generated from operation of the x-ray tube;
A communication device for transmitting a signal to the panel in accordance with the amount of radiation detected by the sensor.   The x-ray system of claim 1, wherein the sensor is configured to detect an amount of radiation generated from activation of the cathode.   The X-ray system according to claim 1, wherein the X-ray tube includes a chamber for housing the anode and the cathode, and the sensor is located in the chamber.   The X-ray system according to claim 1, wherein the X-ray tube includes a chamber for housing the anode and the cathode, and the sensor is located outside the chamber.   The x-ray system of claim 4, wherein the chamber comprises a window to allow the radiation dose to be transmitted from within the chamber to the sensor.   The x-ray system of claim 1, further comprising a circuit for determining whether the detected amount of radiation exceeds a predetermined threshold.   The X-ray according to claim 1, wherein the signal is used to cause the panel to reset an image element of the panel, perform signal integration so as to obtain an image signal, and read the image signal. system.   The X-ray system according to claim 7, wherein the signal is for causing the panel to perform integration of the signal based on a certain integration period.   The X-ray system according to claim 7, wherein the signal is for causing the panel to perform integration of the signal based on a variable integration period.   The x-ray system of claim 9, further comprising a circuit for determining the variable integration period based on a signal generated by the sensor.   The X-ray system according to claim 1, further comprising: the panel, the panel comprising an image element configured to reset the image element after the signal is received for a predetermined period of time.   The x-ray system of claim 11, wherein the predetermined period is at least 100 milliseconds.   The radiation of claim 1, wherein the amount of radiation includes light, and the system further comprises a shielding plate for blocking radiation directed toward the sensor and a mirror for reflecting the light toward the sensor. The described X-ray system. A shaft for holding the cathode;
An optical fiber,
The x-ray system of claim 1, wherein the sensor is coupled to the optical fiber, and one or both of the sensor and the optical fiber are located within the shaft.   The X-ray system of claim 1, wherein the communication device comprises a wired communication path, an RF transmitter, an infrared device, an ultrasonic device, an optical fiber, or a Bluetooth device.   The x-ray system of claim 1, further comprising a device for rotating the anode.   The x-ray system of claim 1, wherein the panel is configured to receive radiation and generate an image signal in response to the received radiation. An X-ray tube having an anode and a cathode;
A sensor configured to sense a condition caused by operation of the x-ray tube;
A communication device for transmitting a signal to the panel based at least in part on the sensed condition, the panel receiving radiation and generating an image signal in response to the received radiation An X-ray system composed of   The x-ray system of claim 18, wherein the sensor comprises a photodetector configured to detect the amount of radiation generated from activation of the cathode.   The x-ray system of claim 18, wherein the sensor comprises a thermal sensor for sensing heat generated from activation of the cathode.   The x-ray system of claim 18, wherein the sensor comprises a current sensor coupled to a current lead, the current lead configured to transmit current to the cathode.   The x-ray system of claim 18, wherein the sensor comprises a current sensor for sensing current delivered to a rotating device configured to rotate the anode.   The x-ray system of claim 18, wherein the sensor comprises a magnetic sensor.   19. The x-ray system of claim 18, further comprising a circuit for determining whether a variable associated with the sensed condition exceeds a predetermined threshold.   19. The X signal according to claim 18, wherein the signal is for causing the panel to reset an image element of the panel, to integrate the signal so as to obtain the image signal, and to read the image signal. Line system.   26. The x-ray system of claim 25, wherein the signal is for causing the panel to integrate the signal based on a certain integration period.   26. The x-ray system of claim 25, wherein the signal is for causing the panel to integrate the signal based on a variable integration period.   28. The x-ray system of claim 27, further comprising a circuit for determining the variable integration period based on the sensed state.   19. The panel further comprising: an image element, the panel being configured to reset the image element after a predetermined period of time has elapsed from the transmission of the signal or the condition being sensed. X-ray system described in 1.   30. The x-ray system of claim 29, wherein the predetermined period is at least 100 milliseconds.   The x-ray system of claim 18, wherein the communication device comprises a wired communication path, an RF transmitter, an infrared device, an ultrasonic device, an optical fiber, or a Bluetooth device. Sensing conditions caused by the operation of the x-ray tube;
Transmitting a signal to the panel in response to the sensed condition, the panel configured to generate an image signal in response to radiation and including a plurality of image elements.   The imaging method according to claim 32, wherein the signal is for causing the panel to reset the image element.   34. The imaging method according to claim 33, wherein the signal is for causing the panel to reset the image element after a predetermined period of time has elapsed from the transmission of the signal or after the state is sensed.   The imaging method according to claim 34, wherein the predetermined period is at least 100 milliseconds.   The imaging method according to claim 34, wherein the signal is for causing the panel to integrate the signal so as to generate the image signal and to read the image signal.   The imaging method of claim 32, further comprising determining a variable integration period based on the sensed state.   The sensed state includes light generated from cathode activation, radiation generated from cathode activation, heat generated from cathode activation, current transmitted to the cathode, and delivered to a rotating device. The imaging method according to claim 32, wherein the imaging method includes a current or a magnetic field.   The imaging method of claim 32, further comprising determining whether a variable associated with the sensed condition exceeds a predetermined threshold.

Images